Showing 35 results for Soil
M Farzadkia, R Rezaee Kalantari, S Jorfi, A.r Talaee, G.r Moussavi,
Volume 2, Issue 1 (7-2009)
Abstract
Background and Objectives : Propylene glycol is the main compound of anti-freezing chemicals. A significant amount of propylene glycol is released to the environment after application and contaminates the soil. The main objective of this study was to determine the biological removal of propylene glycol from wastewater and its degradation in soil by the isolated bacteria from activated sludge process.
Materials and Methods: In the present study, the sludge taken from the return flow in a local activated sludge treatment system was used as the initial seed. The performance of the bioreactor in treating the wastewater was evaluated at four different retention times of 18, 12, 6 and 4 h all with the inlet COD concentration of 1000 mg/L. This phase lasted around 4 months. Then, a part of the adapted microorganisms were transported from the bioreactor to the soil which was synthetically contaminated to the propylene glycol.
Results: The average of propylene glycol removal efficiency from the wastewater in detention times of 18, 12, 8 and 4 h in steady state conditions was 98.6%, 97.1%, 86.4% and 62.2% respectively. Also, the maximum degradation in soil was found to be 97.8%.
Conclusion: According to the results obtained from this study, it appears that propylene glycol is inherently well biodegradable and can be biodegraded in liquid phase and soil after a short period of adaptation.
A. A Pourbabaee, F Karami, A Amirkhani, B Rajabpour,
Volume 3, Issue 2 (7-2010)
Abstract
Backgrounds and Objectives: True cholera with typical clinical features nearly always occurs by serologic groups O1 and O139 but the non-O1 group can produce a disease with same clinical characteristic sporadically. According to the important of climate and environmental conditions in the distribution and abundance of Vibrio cholera, in this study, the distribution of the serologic group was evaluated in different parts of Qom city with relation to the affected patients.
Materials and Methods: In this study 5220 environmental specimens were taken from 12 parts of Qom city and during different seasons of the year 1325, 60 clinical specimens were taken from the patients and all were evaluated for Vibrio cholera with standard methods. The study was of Descriptive and cross sectional and the results were analyzed with statistical soft ware (Epi-info).
Results: The most abundance of Nag strains were related to Emamzadeh Ebrahim and Sheikhabad parts and Shahed Street from Khak faraj and Niroogah area and the least abundance were related to Salariyeh area. The abundance distribution of Nag strain, 7 different specimens was most in hogwash, sewerage and vegetables and least in pipe water which reveal a significant difference (P< 0.05) according to statistical goodness of fit test. The frequency distribution of the patients in each part of area 4 with relevance to sex revealed that the most contamination percentage was attributed to Emamzadeh Ebrahim and Sheikhabad and Shahed from Niroogah area and no positive specimen was taken from Haftado-do-tan and Shahrdary areas.
Conclusion: According to high occurrence of the disease in same areas, and results from other researchers based on increased frequency of non-O1 strains in the environment during the epidemic, so can release a connection between Vibrio cholera O1 strains and non-O1 strains to conclude. On the other hand, none of the clinical and environmental samples, Vibrio cholera O1 was isolated, so probably human carriers in Qom, not the main factor is the emergence of this disease.
Maasoumeh Ravanipour, Roshanak Rezaei Kalantary, Mahdi Farzadkia, Samireh Hashemi-Najafabadi, Ali Esrafily,
Volume 5, Issue 4 (2-2013)
Abstract
MicrosoftInternetExplorer4
Background and Objectives:The poor accessibility of microorganisms to PAHs in soil has limited success in the process of
bioremediation as an effective method for removing pollutants from soils.
Different physicochemical factors are effective on the rate of biodegradation.
The main objective of this study is to assess effects of nutrient and salinity
on phenanthrene removal from polluted soils.
Materials and Methods:The
soil having no organic and microbial pollution was first artificially polluted
with phenanthrene then nutrients and salinity solution in two concentrations
were added to it in order to have the proportion of 10% w:v (soil: water).
After that a microbial mixture enable to degrade phenanthrene was added to the
slurry and was aerated. Finally, the residual concentration of Phenanthrene in
the soil was extracted by ultrasonic and was analyzed using GC. We measured the
microbial populationusing MPN test. This study was conducted based on the two
level full factorial design of experiment.
Results: MPN test
showed that the trend of microbial growth has experienced a lag growth. The
full factorial design indicated that nutrient had the maximum effect on
bioremediation the rate of phenanthrene removal in the maximum nutrients -
minimum salinity solution was 75.14%.
Conclusion: This study
revealed that the more nutrient concentration increases, the more degradation
will be happened by microorganisms in the soils. However, salinity in the
concentration used had no effect on inhabitation or promoting on the
Phenanthrene removal.
Mohammad Reza Mehrasebi, Mansour Baziar, Kazem Naddafi, Mehran Mohammadianfazli, Ali Assadi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and Objectives: Soil pollution by oil compounds is a serious environmental and ground water problem throughout the world. Total petroleum hydrocarbons (TPH) are a combination of many distinctive compounds. Some of these compounds in exposure with human and animal can cause cancer, disorder central nervous system, liver and lungs affects. The objective of this research was to investigate gasoline removal (C10 – C 28) using Brij 35 and Tween 80 from polluted soil. Materials and Methods: In this experimental study, the efficiency of soil washing with nonionic surfactants (Brij 35, Tween 80) for remediation of gasoline polluted soils was studied. The effects of soil washing time, agitation, surfactant concentration, and pH on the removal efficiency were studied. Results: The results showed that gasoline removal efficiency increased with increasing agitation speed and washing time. In addition, it was found that removal efficiency of gasoline was decreased by increasing surfactant concentration. But, increasing pH did not have remarkable effect on removal efficiency of gasoline. The efficiencies of Tween 80 and Brij 35 for removal of gasoline under optimal condition were 70 -80 and 60- 65% respectively. Conclusion: The results showed that soil washing with non ionic surfactants was effective in removal of gasoline from polluted soil and it can be recommended for treating surface soil polluted.
Afsaneh Alinezhadian, Ahmad Karimi, Jahangard Mohammadi, Farzaneh Nikookhah, Mathias Niuman. Anderson,
Volume 6, Issue 3 (12-2013)
Abstract
Background and Objectives: In arid and semi-arid regions, wastewater reuse has become an important element in agriculture. However, irrigation with this resource can be either beneficial or harmful, depending on the wastewater characteristics. The aim of this research was to investigate the soil bacterial and crops quality irrigated with treated wastewater.
Material and Methods: This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer,2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments, well water (W1) with fertilizer and effluent (W2).
Results: At the end of growth season, soil samples were collected from depth of 0-5 and 5-15 cm and plant samples consisting of old and new leaves and seeds were collected for bacteriological analysis. According to bacteriological analysis, total number of positive lactose bacteria, total and fecal coliforms in depth of 0-5 cm was 42% more than depth of 5-15 cm. In the case of old leaves, total number of coliform and fecal coliform was 88 and 40 MPN/100 mL respectively. Moreover, for new leaves, it was 38 and 2 MPN/100 ml respectively.
Conclusion: According the results, number of indicator bacteria in soil is decreased (about 35%) by passing time.
َahmad Joneidi Jafari, Ayooob Rastegar, Mahdi Farzadkia, Roshanak Rezaee Kalantary, Zahra Rezaee Gozalabad,
Volume 6, Issue 4 (3-2014)
Abstract
Background and Objective:Application of compost containing heavy metals can increase the concentration of metals in soil and groundwater. Therefore,the aim of this study was to investigate leaching lead, chromium,and cadmium from three soils (a sandy loam, a sandy clay loam and silt clay loam) amended with compost from the municipal solid waste. Material andMethod:First, the selected soils were repacked into columns (with an inner diameter of 100mm and a height of 600mm). Treatments included(a) low metal content compost (LMCC), (b) enriched metal content compost (EMCC) and (c) control. Then soil columns were incubated at room temperature for 9 days and were irrigated daily with deionized water to make a total of a 250 mm. Leachates were collected and analyzed for pH, EC, Pb, Cr, and Cd concentration. Results: It was found that the application ofEMCCwas significant (p≤0/05) on reducing pH, increasing electrical conductivity and leakage of metalscompared withcontrolin all three soils. But application of LMCC was not significant (p≥0/05) on the metals leaching compared withcontrolin all three soils. The overall quantities of metals leached followed the sandy loam> sandy clay loam> silt clay loam. Conclusion: The concentration of metals in the leachates depended on the soil characteristics and on the type of compost added to the soil. Therefore,application of enriched metal content compost on the soils containinga high percentage ofsandmay pose a risk in terms of groundwater contamination with heavy metals.
S. Jorfi, A. Rezaee, N. Jaafarzadeh Haghighifard, G.a Moheb-Ali,
Volume 7, Issue 3 (5-2014)
Abstract
Background and objectives: Because of problems dealing with bioremediation including being time consuming, low efficiency and toxicity to biota, application of advanced oxidation processes with higher efficiency and shorter remediation time have been considered for removal of hydrophobic hydrocarbons from contaminated soils. A great interest has been directed to Fenton oxidation because of its simplicity and high oxidation potential. The objective of this study was to determine the Fenton-like oxidation efficiency for pyrene removal from soil using iron nano oxides and Fe2+. Material and Methods: The H2O2/Fe molar ratios of unadjusted with native Fe content of soil, 10, and 20 H2O2 concentrations of 0 – 500 mM pH 3, 5, and 7 and soil samples containing Fe2+, native iron and iron nano oxides were investigated for removal of 100 mg/kg pyrene according to Taguchi experimental design. Results: Fe2+, H2O2/Fe molar ratio of 20, pH 3 and H2O2 concentration of 500 mM were determined as optimum conditions. Under optimum conditions, S/N ratio increased to 39.322 and the pyrne removal reached to 86 % for Fe2+ and 83 % for Fe3+ respectively, after 2 hours of reaction time and pH 3. Conclusion: Fenton oxidation using iron nano oxides under defined optimum conditions and neutral pH, can be a suitable alternative to conventional Fenton for remediation of soils contaminated with pyrene.
E Solgi, A Esmaili-Sari, A.r Riyahi Bakhtiari, M Hadipour,
Volume 8, Issue 1 (8-2015)
Abstract
Background and Objectives: Arsenic contamination is of great environmental concern due to its toxic effects as a carcinogen. In order to assess soil arsenic contamination and its distribution patterns, surface soil samples collected from the urban areas of Arak were analyzed. Materials and Methods: Totally, 62 surface soil samples were collected from depth of 0–20 cm of different locations including parks, green spaces, agricultural, roadsides, and squares of Arak City. The spatial distribution of arsenic in soil was mapped using GIS and kriging method. Results: The concentration of arsenic in the surface soil of Arak City was between 2.2- 10.8 mg/kg (average: 5.78 mg/kg). Spatial analysis showed that arsenic contamination enhances in the city center and there was an increasing trend from south to north. In addition, the mean arsenic concentration in the urban topsoil samples from Arak was lower compared with mean concentration for other cities around the world. Conclusion: It seems that arsenic in soil is controlled by natural and anthropogenic factors. The highest concentrations of arsenic in center and the north areas reflected arsenic loading is originated from anthropogenic sources such as vehicles and industrial processes.
M Hatami Manesh, M Mirzaei, M Gholamali Fard, A.r Riyahi Bakhtiyari, M Sadeghi,
Volume 8, Issue 1 (8-2015)
Abstract
Background and Objectives: one of the most important environmental concerns is heavy metals emissions from human activities to natural ecosystems, particularly transfer to soil. The aims of this study were measured the concentrations of Cu, Zn and Cr in landfill soil and hospital waste ash of Shahrekord municipal solid waste landfill. Materials and Methods: Soil samples were collected from three sites: out of the landfill, municipal landfill and hospital landfill. In each site 2, 1, and 1 stations ware selected respectively and each sample was replicated in three times. Results: We found that there was a significant difference between concentrations of Cu, Zn and Cr in the landfills soil (95% confidence, P <0.05). Furthermore, the highest levels of Zn and Cu were detected in the hospital landfill and also for Cr in the municipal landfills. However, the concentration levels of heavy metals in all of the sites were in order as follows: Zn>Cu>Cr. Conclusion: High concentrations of metals determined in the present study represents the high application of these metals in the structure of municipal and hospital solid wastes and also their inaccurate separation. Thus, awareness about physical and chemical characteristics of municipal and hospital wastes and also the landfill soil is necessary for evaluating their effects on the soil quality and surrounding environments.
M Rastegari, M Saeedi, A Mollahosseini,
Volume 8, Issue 2 (8-2015)
Abstract
Background & Objectives: Polycyclic aromatic hydrocarbons (PAHs) are considered as important organic contaminants due to their high toxicity and carcinogenic properties. Among PAHs, phenanthrene is found in most contaminated sites. Sorption and desorption of phenanthrene in soil affect the fate of the contaminant in soil-water system. Presence of organic matter (OM) in the soil matrix can also affect sorption and desorption of phenantherene. In this research, effect of soil organic matter on sorption of phenanthrene in kaolin soil was studied. Materials & Methods: The sorption of sorption of phenanthrene in kaolin clay was assessed in the presence and absence of organic matter. These two soil types were used in batch sorption experiments of Phenanthrene to determine the sorption properties. Results: It was found that organic matter increases the cation exchange capacity, water content, and pH of the soil. Sorption of phenantherene in both kaolin and OM-added kaolin was better fitted with Freundlich linear model. Moreover. soil organic matter increased phenanthrene sorption in soil. Conclusion: It was observed that with 41.04% increase in OM, distribution coefficient of phenanthrene sorption in soil increased by 36.69%.
N Ravankhah, R Mirzaei, S Masoum,
Volume 8, Issue 3 (12-2015)
Abstract
Background and purpose: Soil contamination resulted from either natural or anthropogenic factors reduces environmental quality. The aim of this study was to evaluate the geoaccumulation, contamination factor, and principal component analysis indices to estimate topsoil contamination in Aran-Bidgol town.
Materials and methods: 135 topsoil samples were collected from Aran-Bidgol town and the metal concentrations of Cd, Pb, Ni, Cu, and Zn in each sample were determined. The index of geoaccumulation (Igeo), contamination factor (CF), and principal component analysis (PCA) techniques were applied to determine the status and trends of soil contamination in this region. The inverse distance weighting (IDW) was then used to map these soil contamination indices.
Results: The research found that the means concentrations of Cd, Pb, Ni, Zn, and Cu were 0.72, 11.41, 29.87, 48.59, and 14.82 mg/kg respectively all exceeded the background values. Mean Igeo and CF of elements followed the order: Cu> Cd> Ni> Zn≈ Pb. The Igeo and CF maps showed higher values of Cd, Pb, and Zn in areas near industrial estates, brick kilns, and urban areas whereas higher levels of Cu and Ni occurred in urban and agricultural areas. According to the PCA index, two principal components were identified that Cu, Ni and Zn were highly loaded in PC1 and Cd and Pb occurred in PC2.
Conclusion: Results indicated that the concentration of Pb and Cd are mostly affected by human activities, whereas Ni, Zn, and Cu contents are controlled by both anthropogenic and natural sources.
M.m Amin, M Giyahi, M Mansourian,
Volume 8, Issue 4 (3-2016)
Abstract
Background and Objectives: Perchlorate, as an emerging contaminant, has attracted notice of the most individuals and organizations. Presence of perchlorate in the human body can lead to inappropriate regulation of metabolism in adults. Moreover, due to inhibition of iodide uptake in the thyroid gland, it causes neurological and behavioral problems in infants and children. United States Environmental Protection Agency (EPA) has enacted 15 µg/L perchlorate in drinking water as a guideline value. Regarding the possible sources and potential presence of perchlorate in the environment of the study area, and the unique characteristics of this pollutant, such as extreme water solubility, high mobility in soils and stability in the environment, the status of its contamination was assessed in soil, surface water and drinking water in the study area (Khorramshahr County).
Materials and Methods: Soil and water samples were taken during February to April, 2013. Combined sampling was used for soil sample collection and the random sampling was used for water (surface and drinking water) samples. Each sample was analyzed using ion chromatography. In this study, 15 samples of surface soil and 22 samples of surface and drink water were tested for perchlorate analysis.
Results: It was found that all surface soil and water samples collected from the study area were contaminated with perchlorate and exceed the standard level. Concentration of perchlorate in surface water and drinking water was 1400-5800 and 700-5900 µg/L respectively and in surface soils was 3.3-107.9 mg/kg.
Conclusion: The assessment of perchlorate in soil, surface water, and drinking water in the study area is extremely higher than recommended standards and therefore is a threat to the health of consumers.
L Tabande, M Taheri,
Volume 9, Issue 1 (6-2016)
Abstract
Background and Objective: The contamination of soils and plants with heavy metals is a serious and growing problem. The present study aimed to determine the concentration of heavy metals in soil and some agricultural products and the probability of risks due to their consumption.
Materials and Methods: This cross-sectional descriptive study was performed using random sampling at harvest time in 2014 on 205 samples of vegetable crops (Leek, chard, parsley, watermelon, melon, tomatoes, cucumber, potatoes, onion, garlic, radish, green peas, and broad bean) and 129 samples of soils under cultivation. Concentrations of Cu, Zn, Cd, and Pb in soil and plant samples were determined by an atomic absorption instrument and the data was analyzed using SPSS software.
Results: There were significant differences between the mean concentrations of Pb, Cu, and Zn for different vegetables (P<0.001), but no significant difference was observed for Cd. The highest mean levels of Pb, Cd, Cu, and Zn were detected in parsley, chard, broad bean, and leek respectively. However, there was no heavy metal pollution in the remainder of the vegetables and soil samples (with the exception of agricultural soils adjacent to the lead mine of Mahneshan area) studied. Hazard probability (HQ) of each element for cancerous diseases was less than unit and the intake of heavy metals was lower than the Provisional Tolerable Daily Intake (PTDI).
Conclusion: The results of this study indicated that major accumulation of heavy metals was obtained in leafy vegetables. Therefore, much attention should be paid to consumption of leafy vegetables, especially vegetables grown in the surrounding industrial areas.
N Sistani, M Moeinaddini, N Khorasani, Ah Hamidian, Ms Ali-Taleshi, R Azimi Yancheshmeh,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Urban and industrial development has increased concentration of heavy metals in the environment. The goal of this study was to assess the impact of Kerman steel complex on their surrounding soil by heavy metals.
Materials and Methods: This study was a snapshot and its type was descriptive-analytical research. Heavy metals contents from 60 soil samples (top soil, 0-15 cm) near two Steel Complexes were analyzed using flame atomic absorption spectroscopy (AAS). Source identification and pollution degree indices including enrichment factor (EF) and its percentage (EF%), geo-accumulation index (Igeo), contamination factor (Cf), degree of contamination (Cd) and modified degree of contamination (mCd) were calculated to assess the soil pollution level.
Results: The average concentration of Ni, Zn, Fe, Pb, Cr and Cd were 9.98, 54.38, 15063.33, 20.86, 3.54 and 0.038 mg/kg, respectively. The order of average EF for heavy metals was Pb > Zn> Cd> Fe> Ni> Cr. Cf index also showed that 90% of the samples were moderately to significantly polluted with lead element. The results of EF% indicated that Fe (68.18%) had higher enrichment than others. The average values of Cd and mCd indices were 2.90 and 0.48, respectively, that showed low degree of pollution.
Conclusion: In this study, Pb and Cd concentration were related with activities of the steel complexes and other metals had a combination of natural and anthropogenic emission sources. The steel complexes should plan to reduce pollutants emission to their environment.
Sl Mousavi, A Shakeri, M Nakhaei,
Volume 10, Issue 2 (9-2017)
Abstract
Background and Objective: Polycyclic aromatic hydrocarbons (PAHs) constitute a large class of organic compounds that are composed of two or more fused aromatic rings. Due to their potential mutagenic, carcinogenic and teratogenic effects on human health, PAHs have attracted particular concern. Therefore, in this study it was attempted to measure the PAHs concentration in the study area to evaluate the health risk.
Materials and Methods: 36 samples were taken from the central district in Bandar Abbas county to investigate the degree of contamination, sources and health risk of polycyclic aromatic hydrocarbons (PAHs). Analysis of the samples was performed using gas chromatography. خطای ترجمهAlso, PMF Model was used to determine the possible sources.
Results: The total PAHs concentration had a mean value of 1.48 mg/kg in the soil samples. The total incremental life time cancer risk (ILCR) due to exposure to PAHs in soil is 1.06 × 10−6 for an adult and 4.95 × 10−6 for children. The results estimated for ILCR indicated that residents live in the central district of Bandar Abbas county are potentially exposed to cancer risk via both dust ingestion and dermal contact.
Conclusion: The ecological risk assessment of PAHs showed that the levels of all types of PAHs were lower than the lower value of effects range, except for dibenzo(a,h) antheracene and acenaphthene. The estimated results of ILCR indicated that Bandar Abbas county central district residents are potentially exposed to cancer risk via both ingestion and dermal contact. The PMF analysis identified four sources that were included fossil fuel combustion (14%), biomass combustion (13%), vehicular emissions (36%) and fossil fuel combustion/unburned petroleum (37%).
Ar Mansoorian, A Vaziri, Mr Zamani, F Heidaryan Naeini,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: In the field of environmental risk assessment, Cyanide is one of the most important pollutants of water, soil and air that has an important impact on the ecosystem and environment of the contaminated area. Therefore, the present study aimed to prove the biological effectiveness of Vetiveria zizanioides in phytoremediation of soils contaminated with cyanide.
Materials and Methods: This research study was conducted on a gold mine wastewater. The dried effluent samples amended with soil with various cyanide concentrations. Seven treatments with different concentrations of cyanide were obtained (mean cyanide content in G soil, 14.77 mg/kg, F soil, 10.13 mg/kg, E soil, mg/kg 8.09, D soil, mg/kg 7.53, C soil, 3.32 mg/kg, B soil, 2.52 mg/kg and A soil without cyanide (as control). After two months, the amount of cyanide in the soil, roots and leaves of the plant, as well as the total protein and proline content, and the number and length of the leaves of the plant were measured and then statistically evaluated by SPSS15 Tukey and t Paired Samples T Tests.
Results: The results of this study showed that the increase of cyanide had a significant effect on the amount of proline (proline in the plant increased), total protein (in the plant increased), number of leaves (decrease in number) and the length (length reduction) of the leaves of the vetiver. The amount of cyanide in the leaves and roots of the plant was increased. Cyanide content was decreased in the different treatments. Cyanide content was decreased in G 50.93%, F 38.20%, E 27.19%, D 38.37%, C 17.77% and B 16.66%.
Conclusion: The results indicated that increase of the amount of cyanide in soil resulted in observational changes in the morphological and biochemical characteristics of the plant. However, Vetiveria zizanioides exhibited very high resistance to soil cyanide and the planting of vetiver in highly contaminated soils can lead to a reduction of cyanide up to 50 percent. Vetiveria zizanioides had higher resistance to cyanide and showed better phytoremediation than the other plants.
B Mohammad Moradi, S Sobhanardakani, M Cheraghi,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Heavy metals are the most frequent pollutants of urban soils. In general, human health and especially children are directly at risk if the soil is being accidentally ingested orally or nasally. Therefore, this study was conducted to assess potential ecological risk index (RI) of Pb, Cd, Cr and Cu in surface soils of urban parks in Tehran City in 2016.
Materials and Methods: A total of 60 surface soil samples were collected from Mellat, Laleh, Velayat, Ekbatan and Pirouzi parks. The heavy metals contents in samples were determined using ICP-OES after acid digestion of soil samples. Also, RI of heavy metals was determined. All statistical analyses were performed according to the Shapiro-Wilk test, One-Way ANOVA, One Sample T-Test and Pearson Correlation Coefficient.
Results: The lowest and highest contents of the metals (mg/kg) with an average of 0.52 ± 0.25 and 153.81 ± 31.83 were related to Cd and Pb, respectively. Pb and Cu were higher than MPL. Also, the highest surface soil contamination was related to Velayat Park located at the south of Tehran. The value of RI was 99.16 and therefore the soil contamination was categorized in low ecological risk.
Conclusion: Although the value of RI categorized as low ecological risk, due to mean concentrations of Pb and Cu were higher than MPL, control of soil-contamination sources, periodic monitoring of surface soil in the urban parks where citizens spend most of their free time. Additionally, it should be avoided to construct urban parks close to the regions with high traffic intensity.
Ah Baghaie,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: Today, landfill management of municipal waste and soil pollution with heavy metals are major environmental problems. This research was conducted to evaluate the effect of Shazand municipal waste compost and Saveh pomegranate peel biochar on decreasing Pb availability in soil and sorghum plant.
Materials and Methods: Treatments consisted of applying Shazand municipal waste compost (0, 10 and 20 ton/ha) and Saveh pomegranate peel biochar (0 and 15 g/kg) in a Pb polluted soil (0, 600, 800 and 1000 mg Pb/kg soil). After 8 weeks of sorghum planting (Kimya CV.), the soil physio-chemical properties and soil and plant Pb concentration were measured.
Results: Applying 20 ton/ha municipal waste compost with 15 g/kg biochar increased soil pH by 0.4 units and decreased soil Pb availability by 11%. The similar results were observed for the root and shoot Pb concentrations, when the same amount of manure in a Pb polluted soil was applied (1000mg Pb/kg soil) that decreased the root and shoot Pb concentration by 1.8 and 2.2 times, respectively.
Conclusion: The result of this experiment showed that applying Shazand municipal waste compost and biochar can increase soil sorption properties and decrease soil or plant Pb concentration. However, the role of these organic amendments on supplying plant nutritional needs cannot be ignored.
Ghr Siyahati Ardakani, M Mirsanjari, Hr Azimzadeh, E Solgi,
Volume 11, Issue 3 (12-2018)
Abstract
Background and Objective: The establishment of pelletizing and steel industries in Ardakan suburbs has increased the pollutants such as heavy metals into the environment. The purpose of this study was to investigate the contamination of the area soil by heavy elements around these industries using the pollution index (PI), comprehensive pollution index (NIPI), accumulation index (Igeo) and enrichment index (EF).
Materials and Methods: 57 soil samples were prepared by systematic-random sampling from 0 to 5 cm depth and levels of As, Cd, Cr, Mo, Ni, Pb, V and Zn were analyzed by ICP-OES.
Results: The highest and lowest mean of Igeo (0.49 and 0.36) and PI (2.16 and 1.17), were related to nickel, and the highest EF was calculated for Zn at about 25.1 and the lowest were detected for molybdenum approximately that was 17.1. The EF index of lead, vanadium and zinc, which was 15.8%, 5.3% and 1.8%, respectively, classified the study area in a medium enrichment class. Hot spots of lead, vanadium, nickel and zinc was at the nearest distance to these industries and downstream of wind direction.
Conclusion: Indicators of Igeo and EF showed a low level of soil pollution. The PI and NIPI indices in most stations were classified in medium pollution class, and the highest of these indicators was related to the surface soil of station 30, which was located near the steel industry. Therefore, it can be concluded that the activities of these industries had affected the soil contamination of the study area.
Bahareh Ghoreishi, Hassan Aslani, Mohammad Shaker Khatibi, Sepideh Nemati Mansur, Mohammad Mosaferi,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: Application of sewage sludge contaminated with heavy metals may cause health and ecological concern. Ecological risk and heavy metals content of sewage sludge from wastewater treatment plants of East Azerbaijan province were evaluated in the present study.
Materials and Methods: Nine composite samples were taken and analyzed for heavy metals. The geo-accumulation index (Igeo), contamination factor(CF) , and potential ecological risk index were calculated.
Results: Variation of the heavy metals concentrations were in the following order: Zn>Cu>Pb>Cr>Ni>As>Hg>Cd. The contents of some heavy metals were several order of magnitude higher than the crustal average (CA) values. Considering the Maximum Permissible Standards (MPS) and the Muller's index, the Cd, Cu, and Zn pollution were found to be in the moderate range, whereas As and Pb were in strongly polluted category; and Hg was in extremely polluted category. Considering MPS, the single-factor pollution index (PI) and the Nemerow’s synthetic pollution index (PN) were lower than 1 and 0.7 respectively. This indicated that the sludges were unpolluted with most heavy metals and could be safely applied for agricultural uses. However, a high potential ecological risk for As and Cd; very high risk for Pb; and extremely high risk for Hg were calculated when considering the CA values. There were significant differences between the levels of heavy metals and MPS (p <0.05).
Conclusion: Although the metal concentrations were below the MPS according to the US EPA regulations, sludge samples showed a high degree of potential ecological risk for the environment in comparision with the CA values,. Periodic monitoring of sludge quality are strongly recommended.
